Battery pack recovery processing method and device system

Abstract

The invention provides a battery pack recovery processing method and device system.The battery pack recovery processing method comprises the steps that S1, pretreatment is conducted, specifically, voltage balance adjustment, whole pack discharging and cover removing treatment are conducted on a battery pack in sequence, and an uncovered battery pack is obtained; s2, carrying out gradient pyrolysis on the whole battery pack: sequentially carrying out low-temperature drying, medium-temperature debonding and high-temperature pyrolysis on the uncovered battery pack to obtain an intermediate battery pack and pyrolysis gas; s3, crushing the whole battery pack: performing multi-stage crushing treatment on the intermediate battery pack to obtain a crushed material; and S4, sorting treatment is conducted, specifically, the crushed materials are subjected to multi-stage precise sorting, and a black powder product is obtained. According to the method, a combined process of whole pack pretreatment, staged whole drying pyrolysis, staged crushing and multi-stage precise sorting is adopted, so that the process flow is simplified, the energy consumption and the cost are reduced, and the suitability of the battery pack recovery process and the black powder recovery rate are improved.

Description

Technical Field

[0001] This invention belongs to the field of battery recycling technology and relates to a battery pack recycling method and apparatus system. Background Technology

[0002] The recycling of retired power batteries is a key link in promoting the healthy, green, and sustainable development of the entire new energy vehicle industry. However, existing recycling methods have several shortcomings that seriously reduce the effectiveness of battery recycling.

[0003] (1) Traditional processes are lengthy and costly to dismantle: Existing mainstream recycling processes all follow the path of "battery pack dismantling → cell sorting → cell crushing → low-temperature drying → medium-temperature pyrolysis". The dismantling process requires the investment of automatic cap removal machines and cell separation robotic arms, resulting in high labor costs and a cell damage rate of over 5%. In addition, the entire process involves 11 to 13 steps, with a large number of equipment, dense fault points, and an uptime rate of only 80%. Conventional dismantling processes are prone to electrolyte leakage and short circuit fires, and the process costs are high. Furthermore, the existing battery recycling processes only target waste batteries and do not consider the modular integration characteristics of battery packs.

[0004] (2) High energy consumption and easy clogging of tail gas in staged pyrolysis: Existing technologies generally adopt a two-stage process of "low temperature drying (200~250℃) + medium temperature pyrolysis (400~450℃)," which generally has high energy consumption. Under the traditional "crush first and then dry" mode, the amount of dust generated is ≥15kg / ton, and the fluoride in the electrolyte is easy to condense in the low temperature pipeline (<400℃), which leads to the clogging frequency of the tail gas bag filter up to 1 time / day, which increases the maintenance cost by 20%. If high temperature single pyrolysis is used, it is easy to cause the high boiling point solvent to not evaporate fully and the low boiling point solvent to decompose excessively. In addition, the high temperature oxidation of lithium iron phosphate reduces the wet leaching recovery rate, and the high temperature easily causes the aluminothermic reaction, resulting in thermal runaway.

[0005] (3) Low black powder yield and serious waste of resources: The direct black powder yield of the existing production line is only over 85%, and the lithium content in copper-aluminum slag is 0.61~0.78%. If the black powder yield is to be increased, an additional grinding machine is required, which will increase the equipment investment by 15%. Moreover, the residual black powder in copper-aluminum slag is still very high, reaching 0.8~1.0%.

[0006] (4) The whole package crushing technology is immature and the safety is insufficient: the existing technology has not solved the temperature rise problem of whole package crushing with electricity, and there is no nitrogen dynamic adjustment system. If the oxygen content exceeds the standard, there is a risk of combustion and explosion.

[0007] (5) Incomplete exhaust gas treatment: The existing recovery process only recovers organic solvents by cooling, which cannot treat low-boiling-point VOCs and pyrolysis by-products (such as fluorides), which can easily cause secondary pollution.

[0008] Therefore, it is very important to provide a high-recycling-rate, low-cost, green and energy-saving retired battery recycling process line. Summary of the Invention

[0009] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a battery pack recycling method and device system. By combining whole pack pretreatment, staged drying and pyrolysis, graded crushing and multi-stage precision sorting, the process flow is simplified, energy consumption and cost are reduced, and the defects of poor adaptability, low efficiency and insufficient environmental protection of battery pack recycling process are solved.

[0010] To achieve this objective, the present invention adopts the following technical solution:

[0011] In a first aspect, the present invention provides a battery pack recycling method, the battery pack recycling method comprising:

[0012] S1 Pre-processing: The battery pack is subjected to voltage equalization adjustment, full pack discharge and cover removal in sequence to obtain a coverless battery pack.

[0013] S2 Gradient pyrolysis of the entire battery pack: The uncovered battery pack is sequentially subjected to low-temperature drying, medium-temperature debinding and high-temperature pyrolysis to obtain an intermediate battery pack and pyrolysis gas.

[0014] S3 Whole Pack Crushing: The intermediate battery pack is subjected to multi-stage crushing to obtain crushed material.

[0015] S4 sorting process: The crushed material is subjected to multi-stage precision sorting to obtain black powder product.

[0016] This invention pre-treats and gradient pyrolysis of the entire battery pack, eliminating the need for individual battery cell disassembly. It simultaneously completes the evaporation of the electrolyte and the pyrolysis of the binder, separator, and blue film, greatly simplifying the battery recycling process, reducing metal oxidation, and improving separation efficiency.

[0017] As a preferred embodiment of the present invention, the voltage equalization adjustment includes: detecting the voltage value of each cell in the battery pack to obtain the voltage deviation between the cells; determining whether the voltage deviation is greater than a preset voltage difference; if so, activating the equalization circuit to adjust the voltage of the cells in the battery pack until the voltage deviation does not exceed the standard voltage difference, and then discharging the entire battery pack; otherwise, directly discharging the entire battery pack.

[0018] As one embodiment of the present invention, the preset voltage difference is 0.2~0.3V, for example, it can be 0.2V, 0.23V, 0.25V, 0.26V or 0.3V, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0019] As one embodiment of the present invention, the standard voltage difference is 0.1~0.2V, for example, it can be 0.1V, 0.13V, 0.15V, 0.18V or 0.2V, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0020] This invention ensures balanced cell voltage within the battery pack, avoiding extreme voltages that could reduce the overall discharge performance of the battery pack.

[0021] As one embodiment of the present invention, the whole-pack discharge includes pulse discharge processing.

[0022] As one embodiment of the present invention, the current of the pulse discharge treatment is 50~80A, for example, it can be 50A, 52A, 55A, 58A, 60A, 65A, 70A, 75A, 78A or 80A, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0023] As one embodiment of the present invention, the pulse discharge treatment time is 2 to 3 hours, for example, it can be 2.0 hours, 2.1 hours, 2.2 hours, 2.3 hours, 2.4 hours, 2.5 hours, 2.7 hours, 2.8 hours, 2.9 hours or 3.0 hours, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0024] As one embodiment of the present invention, after the pulse discharge process ends, the voltage of the battery pack is 2.8~3V, for example, it can be 2.80V, 2.82V, 2.85V, 2.88V, 2.90V, 2.95V, 2.98V or 3.00V, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0025] As a preferred embodiment of the present invention, the preprocessing further includes: after the entire battery pack is discharged, performing a supplementary discharge process on the battery pack with a voltage value greater than 3V, and detecting the voltage of each cell in the battery pack to ensure that its voltage is less than 3V.

[0026] As one embodiment of the present invention, the current of the discharge treatment is 30~50A, for example, it can be 30A, 32A, 35A, 36A, 38A, 40A, 42A, 45A, 48A or 50A, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0027] As one embodiment of the present invention, the pretreatment further includes: sequentially draining coolant from the coverless battery pack, removing wiring harnesses, and punching holes in the safety valve.

[0028] As one embodiment of the present invention, the pumping rate of the coolant is 5~8L / min, for example, it can be 5.0L / min, 5.2L / min, 5.5L / min, 5.8L / min, 6.0L / min, 6.3L / min, 6.7L / min, 7.0L / min, 7.5L / min or 8.0L / min, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0029] As one embodiment of the present invention, the wiring harness removal includes removing the battery pack BMS (Battery Management System) assembly and the high and low voltage wiring harnesses.

[0030] As one embodiment of the present invention, the diameter of the through hole formed by punching the safety valve is 2~3mm, for example, it can be 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm or 3.0mm, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0031] As a preferred embodiment of the present invention, the low-temperature drying, the medium-temperature debonding, and the high-temperature pyrolysis are each performed independently by purging the coverless battery pack with nitrogen.

[0032] In one embodiment of the present invention, the temperatures and nitrogen flow rates of the low-temperature drying, the medium-temperature debonding, and the high-temperature pyrolysis are different.

[0033] As one embodiment of the present invention, the temperature of the low-temperature drying is 80~120℃, for example, it can be 80℃, 82℃, 85℃, 88℃, 90℃, 95℃, 98℃, 100℃, 105℃ or 120℃, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0034] As one embodiment of the present invention, the low-temperature drying time is 30~40 min, for example, it can be 30 min, 31 min, 32 min, 33 min, 34 min, 35 min, 36 min, 37 min, 38 min or 40 min, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0035] As one embodiment of the present invention, the nitrogen flow rate for low-temperature drying is 50~60 m³ / h, for example, it can be 50 m³ / h, 51 m³ / h, 52 m³ / h, 53 m³ / h, 54 m³ / h, 55 m³ / h, 56 m³ / h, 57 m³ / h, 58 m³ / h or 60 m³ / h, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0036] As one embodiment of the present invention, the temperature for medium-temperature debonding is 200~280℃, for example, it can be 200℃, 205℃, 210℃, 215℃, 220℃, 230℃, 240℃, 250℃, 260℃ or 280℃, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0037] As one embodiment of the present invention, the medium-temperature debonding time is 25~35min, for example, it can be 25min, 26min, 27min, 28min, 29min, 30min, 31min, 32min, 33min or 35min, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] As one embodiment of the present invention, the nitrogen flow rate for the intermediate-temperature debonding is 70~80 m³ / h, for example, it can be 70 m³ / h, 71 m³ / h, 72 m³ / h, 73 m³ / h, 74 m³ / h, 75 m³ / h, 76 m³ / h, 77 m³ / h, 78 m³ / h or 80 m³ / h, etc., but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0039] As one embodiment of the present invention, the temperature of the high-temperature pyrolysis is 300~400℃, for example, it can be 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, 360℃, 370℃, 380℃ or 400℃, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0040] As one embodiment of the present invention, the high-temperature pyrolysis time is 20~30min, for example, it can be 20min, 21min, 22min, 23min, 24min, 25min, 26min, 27min, 28min or 30min, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0041] As one embodiment of the present invention, the nitrogen flow rate for the high-temperature pyrolysis is 90~100 m³ / h, for example, it can be 90 m³ / h, 91 m³ / h, 92 m³ / h, 93 m³ / h, 94 m³ / h, 95 m³ / h, 96 m³ / h, 97 m³ / h, 98 m³ / h or 100 m³ / h, etc., but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0042] As one embodiment of the present invention, the water content of the intermediate battery pack is ≤0.5%, for example, it can be 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0043] This invention selectively evaporates the electrolyte through low-temperature drying, efficiently removes binder decomposition products from the battery pack through medium-temperature debonding, and deeply decomposes the binder through high-temperature pyrolysis to reduce metal oxidation. Simultaneously, it independently controls parameters such as the processing temperature, time, and nitrogen flow rate for low-temperature drying, medium-temperature debonding, and high-temperature pyrolysis, adapting to the separation of solvents and binders at different depths within the entire battery pack. This improves separation efficiency, achieving a binder removal rate of over 99% and effectively reducing the water content in the battery.

[0044] As a preferred embodiment of the present invention, the battery pack recycling method further includes: treating the pyrolysis gas in a co-processing manner before discharging it.

[0045] As one embodiment of the present invention, the exhaust gas co-treatment includes high-temperature dust removal, incineration, waste heat recovery, rapid cooling, and exhaust gas deacidification and alkali spraying treatment performed sequentially.

[0046] As one embodiment of the present invention, the temperature of the high-temperature dust removal is 400~420℃, for example, it can be 400℃, 403℃, 405℃, 408℃, 410℃, 412℃, 415℃, 417℃, 418℃ or 420℃, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0047] As one embodiment of the present invention, the incineration temperature is ≥850℃, for example, it can be 850℃, 880℃, 1000℃, 1200℃, 1500℃, 2000℃, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0048] The residence time for incineration is >2.5s, for example, it can be 3s, 4s, 5s, 6s, 7s, 8s, 10s, 20s, 30s or 40s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0049] As one embodiment of the present invention, after the rapid cooling is completed, the temperature of the pyrolysis gas is below 200°C, for example, it can be 80°C, 100°C, 120°C, 140°C, 160°C, 180°C, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0050] In one embodiment of the present invention, the tail gas deacidification includes spraying lime onto the pyrolysis gas.

[0051] As one embodiment of the present invention, the pH of the alkali source used in the alkali spraying treatment is 8.5 to 9, for example, it can be 8.5, 8.6, 8.7, 8.8, 8.9 or 9, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0052] This invention directly purifies pyrolysis gas, achieving efficient dust removal and preventing fluoride condensation and blockage. It decomposes organic pollutants through incineration, then cools the flue gas to inhibit dioxin formation, followed by acid removal, dust removal, and alkaline scrubbing to further remove fluorides, ensuring that the emission concentration meets the requirements. It also avoids the problem of dust leakage caused by material transfer.

[0053] As a preferred embodiment of the present invention, the battery pack recycling and processing method further includes: acquiring basic information about the battery pack and constructing a parameter database that automatically matches the operating parameters of the pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting, and exhaust gas co-processing processes for different battery packs; collecting real-time operating parameters during the pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting, and exhaust gas co-processing processes; and, based on the real-time operating parameters and the parameter database, performing coordinated control on the operating parameters of the pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting, and exhaust gas co-processing processes.

[0054] As a preferred embodiment of the present invention, the multi-stage crushing process includes: performing primary crushing on the intermediate battery pack to obtain coarse crushed material, and performing secondary crushing on the coarse crushed material to obtain the crushed material.

[0055] As one embodiment of the present invention, the average particle size of the coarse crushed material is ≤100mm, for example, it can be 50mm, 60mm, 70mm, 80mm, 90mm or 100mm, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0056] In one embodiment of the present invention, the average particle size of the crushed material is ≤50mm, for example, it can be 10mm, 20mm, 30mm, 40mm, 45mm or 50mm, etc., but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0057] As one embodiment of the present invention, water cooling and nitrogen protection are performed in both the primary crushing and the secondary crushing processes.

[0058] As one embodiment of the present invention, the inlet water temperature of the water cooling treatment is ≤30℃, for example, it can be 5℃, 8℃, 10℃, 12℃, 15℃, 20℃, 24℃, 25℃, 28℃ or 30℃, etc., but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0059] The outlet water temperature of the water cooling treatment is ≤45℃, for example, it can be 20℃, 24℃, 25℃, 28℃, 30℃, 35℃, 38℃, 40℃, 44℃ or 45℃, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0060] As one embodiment of the present invention, the nitrogen flow rate used for nitrogen protection is 120~150 m³ / h, for example, it can be 120 m³ / h, 125 m³ / h, 128 m³ / h, 130 m³ / h, 132 m³ / h, 135 m³ / h, 138 m³ / h, 140 m³ / h, 145 m³ / h or 150 m³ / h, etc., but it is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0061] As a preferred technical solution of the present invention, the multi-stage precision sorting includes: performing a first-stage sorting on the crushed material to obtain coarse particles and battery cell fragments, separating the coarse particles, performing a second-stage sorting on the battery cell fragments to obtain mixed fragments and primary black powder, separating the primary black powder, and performing a third-stage sorting on the mixed fragments to obtain metallic materials and black powder products, separating the metallic materials.

[0062] As one embodiment of the present invention, the screen aperture of the primary sorting is 8~12mm, for example, it can be 8mm, 9mm, 10mm, 11mm or 12mm, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0063] As one embodiment of the present invention, the screen aperture of the secondary sorting is 4~6mm, for example, it can be 4mm, 4.5mm, 5mm, 5.5mm or 6mm, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0064] As one embodiment of the present invention, the screen aperture of the three-stage sorting is 1~2mm, for example, it can be 1mm, 1.5mm or 2mm, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0065] As one embodiment of the present invention, the multi-stage precision sorting further includes: purifying the primary black powder to obtain a black powder product.

[0066] As one embodiment of the present invention, the sieve aperture used in the purification process is 0.1~0.2mm, for example, it can be 0.1mm, 0.12mm, 0.15mm, 0.18mm or 0.2mm, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0067] As one embodiment of the present invention, the copper content in the black powder product is ≤0.8%, for example, it can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% or 0.8%, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0068] The aluminum content in the black powder product is ≤0.7%, for example, it can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6% or 0.7%, etc., but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0069] This invention achieves a black powder yield of ≥98% through multi-stage sorting, reduces the lithium content in the residue, and effectively improves the purity of the metal materials.

[0070] In a second aspect, the present invention provides a battery pack recycling and processing device system, which is used in the battery pack recycling and processing method described in the first aspect. The battery pack recycling and processing device system includes a pretreatment unit, a pyrolysis unit, a crushing unit, and a sorting unit connected sequentially along the battery pack conveying direction.

[0071] The pretreatment unit includes a voltage equalization regulating device, a whole-pack discharge device, and a cap removal device connected sequentially along the battery pack conveying direction. The pyrolysis unit includes a continuous pyrolysis device, which comprises a low-temperature zone, a medium-temperature zone, and a high-temperature zone arranged sequentially. The crushing unit includes a multi-stage crushing device. The sorting unit includes a multi-stage sorting device.

[0072] As a preferred embodiment of the present invention, the battery pack recycling and processing device system further includes an intelligent control unit, which is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit and the sorting unit respectively.

[0073] In one embodiment of the present invention, the intelligent control unit includes a data acquisition module, a parameter calculation module, and a control module. The data acquisition module is electrically connected to the preprocessing unit, the pyrolysis unit, the crushing unit, and the sorting unit, respectively, and is used to acquire basic information of the battery pack and real-time operating parameters of each processing unit. The parameter calculation module is electrically connected to the data acquisition module and the control module, respectively, and is used to construct a parameter database based on the basic information of the battery pack and automatically match the standard operating parameters of the preprocessing unit, the pyrolysis unit, the crushing unit, and the sorting unit. The control module is electrically connected to the preprocessing unit, the pyrolysis unit, the crushing unit, and the sorting unit, respectively, and is used to adjust the operating parameters of the preprocessing unit, the pyrolysis unit, the crushing unit, and the sorting unit.

[0074] As one embodiment of the present invention, the battery pack recycling and processing device system further includes an exhaust gas treatment unit, which is connected to the pyrolysis unit.

[0075] In one embodiment of the present invention, the exhaust gas treatment unit includes a dust removal device, an incineration device, a cooling device, an acid removal device, and an alkali spraying device connected in sequence, and the incineration device is externally connected to a waste heat recovery device.

[0076] As one embodiment of the present invention, the pretreatment unit further includes a supplementary discharge device disposed between the whole package discharge device and the cap removal device.

[0077] In one embodiment of the present invention, the pretreatment unit further includes a pumping device, a wire harness removal device, and a punching device connected in sequence. The inlet end of the pumping device is connected to the cap removal device, and the outlet end of the punching device is connected to the pyrolysis unit.

[0078] In one embodiment of the present invention, the multi-stage crushing device includes a primary crushing device and a secondary crushing device connected in sequence, wherein the primary crushing device is connected to the pyrolysis unit and the secondary crushing device is connected to the sorting unit.

[0079] In one embodiment of the present invention, the primary crushing device and the secondary crushing device are respectively provided with a cooling component and a nitrogen protection component.

[0080] As one embodiment of the present invention, the multi-stage sorting device includes a primary sorting device, a secondary sorting device, a tertiary sorting device, and a purification device, wherein the primary sorting device is connected to the crushing unit.

[0081] As one embodiment of the present invention, the battery pack recycling and processing device system further includes a fault early warning unit, which is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit and the sorting unit respectively.

[0082] The system refers to an equipment system, device system, or production device.

[0083] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0084] This invention provides a battery pack recycling method and apparatus system that pyrolyzes the entire battery pack, eliminating the traditional individual battery dismantling process, shortening the battery recycling process, reducing the number of equipment by 40%, and increasing equipment utilization from 80% to over 92%, thereby reducing process energy consumption and costs. Based on a combined process of whole pack pretreatment—whole pack drying and pyrolysis—whole pack crushing—multi-stage precision sorting, the black powder recovery rate is increased to ≥98%, the residual black powder content in the product residue is ≤0.5% (lithium content ≤0.3%), the purity of recovered copper is ≥96%, and the purity of aluminum is ≥95%, achieving efficient resource recovery and greatly improving work efficiency. Attached Figure Description

[0085] Figure 1 This is a flowchart of the battery pack recycling method provided in Example 1. Detailed Implementation

[0086] It should be understood that in the description of this invention, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0087] It should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0088] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0089] In one specific embodiment, the present invention provides a battery pack recycling method, which specifically includes the following steps:

[0090] S1 Pre-processing: The battery pack is subjected to voltage equalization adjustment, full pack discharge and cover removal in sequence to obtain a coverless battery pack.

[0091] The voltage equalization adjustment method includes: detecting the voltage value of each cell in the battery pack to obtain the voltage deviation between cells; determining whether the voltage deviation is greater than a preset voltage difference; if so, activating the equalization circuit to adjust the voltage of the cells in the battery pack until the voltage deviation does not exceed the standard voltage difference, then discharging the entire battery pack; otherwise, directly discharging the entire battery pack. Specifically, the preset voltage difference is 0.2~0.3V, and the standard voltage difference is 0.1~0.2V.

[0092] The entire battery pack is discharged using a pulse discharge process. Specifically, the pulse discharge current is 50-80A and the duration is 2-3 hours. After the pulse discharge process ends, the voltage of the battery pack decreases from 3.2-3.3V to 2.8-3V.

[0093] Furthermore, after the entire battery pack is discharged, the battery packs with voltage values ​​greater than 3V undergo a supplementary discharge process, and the voltage of each cell within the battery pack is detected to ensure that its voltage is less than 3V. The current for the supplementary discharge process is set to 30~50A.

[0094] The battery pack removal process uses a robotic arm combined with laser positioning technology commonly used in the field to remove the battery pack cover, ensuring an accuracy of ±2mm and avoiding damage to the internal cells. Compared with traditional battery cell disassembly, this reduces the disassembly difficulty.

[0095] In some embodiments, the uncovered battery undergoes sequential coolant drainage, wiring harness removal, and safety valve puncture. Specifically, the coolant drainage utilizes a commonly used negative pressure drainage device to extract coolant from the battery pack at a drainage rate of 5-8 L / min. The collected coolant is then outsourced for processing to prevent boiling and splashing during pyrolysis, which could lead to coking inside the furnace. Wiring harness removal involves using a robotic arm to remove the battery pack BMS assembly and high- and low-voltage wiring harnesses, which are then sorted and recycled. The BMS assembly, as is well known to those skilled in the art, is the hardware entity of a battery management system, integrating circuit boards, chips, sensors, communication interfaces, and other components. It is directly installed inside the battery pack, and the entire structure can be removed using a robotic arm. The safety valve puncture is performed using a commonly used automatic puncture machine to puncture the safety valve of the battery cell, creating a through hole with a diameter of 2-3 mm. This hole releases internal pressure within the battery cell, preventing bulging and rupture during pyrolysis.

[0096] S2 Gradient pyrolysis of the entire battery pack: The uncovered battery pack is sequentially subjected to low-temperature drying, medium-temperature debinding and high-temperature pyrolysis to obtain an intermediate battery pack and pyrolysis gas.

[0097] This invention employs a continuous tunnel kiln with a zoned heating design to achieve low-temperature drying, medium-temperature debonding, and high-temperature pyrolysis of battery packs. The low-temperature drying, medium-temperature debonding, and high-temperature pyrolysis are each achieved independently by purging the uncovered battery pack with nitrogen. Traditional pyrolysis methods using natural gas and tail gas heating experience temperature fluctuations of ±30℃, requiring frequent manual adjustments and lacking dynamic nitrogen control, easily resulting in oxygen content exceeding 3% within the furnace. This invention divides the continuous tunnel kiln into three sections with independent temperature and nitrogen flow control, ensuring a stable oxygen content within the furnace ≤3%. The kiln body can utilize a fluorine-resistant lining, extending its service life to 5 years and reducing equipment replacement costs. For conventional battery structures where the electrolyte boiling point is 200-300℃ and the binder boiling point is 380-420℃, this invention independently controls the temperature and nitrogen flow rate at different processing stages. This ensures that the temperatures and nitrogen flow rates for low-temperature drying, medium-temperature debonding, and high-temperature pyrolysis are different, simultaneously achieving electrolyte evaporation and pyrolysis of the binder, separator, or blue film, thus improving separation efficiency. This invention directly skips the process of disassembling the battery pack into individual battery cells, dries the entire battery pack, and simultaneously completes the evaporation of the electrolyte, as well as the pyrolysis of the separator, blue film, and binder. This reduces equipment investment by 30%, significantly streamlines the battery pack processing flow, and dramatically improves processing efficiency.

[0098] Furthermore, the low-temperature drying temperature is 80~120℃, the nitrogen flow rate is 50~60 m³ / h, and the time is 30~40 min, which can selectively evaporate the free electrolyte, such as dimethyl carbonate and ethyl methyl carbonate. The medium-temperature debonding temperature is 200~280℃, the nitrogen flow rate is 70~80 m³ / h, and the time is 25~35 min, which can efficiently remove the binder. The high-temperature pyrolysis temperature is 300~400℃, the nitrogen flow rate is 90~100 m³ / h, and the time is 20~30 min, which can deeply decompose the binder. Compared with a single pyrolysis treatment method, the pyrolysis temperature of this invention is lower, which can reduce metal oxidation. The pyrolysis process combined with nitrogen purging, through the "temperature-flow rate" gradient adjustment, effectively improves the separation effect. The water content of the intermediate battery pack after pyrolysis is ≤0.5%, and the binder removal rate is ≥99%.

[0099] In some embodiments, the battery pack recycling method further includes: treating the pyrolysis gas in a co-processing manner before discharging it, wherein the co-processing manner includes sequential high-temperature dust removal, incineration, waste heat recovery, rapid cooling, and acid and alkali spraying of the exhaust gas.

[0100] Specifically, the high-temperature dust removal uses ceramic filter tubes commonly used in the field, filtering and removing dust from the pyrolysis gas at a temperature of 400~420℃, with a dust removal rate ≥98%, while also preventing fluoride condensation and blockage. The incineration process uses a secondary combustion chamber, ensuring a temperature ≥850℃ and a residence time >2.5s, decomposing organic pollutants such as electrolyte solvents, with a removal rate ≥99.95%. Waste heat recovery utilizes a waste heat boiler to generate 0.8MPa saturated steam from the flue gas for use in other workshops, with a waste heat recovery rate ≥75%. This invention rapidly cools the pyrolysis gas after waste heat recovery, reducing its temperature from 850℃ to below 200℃ within 2s, inhibiting dioxin formation. This invention also sprays lime onto the pyrolysis gas to achieve tail gas deacidification, with a deacidification efficiency ≥96%, effectively removing fluorides. The alkaline spray treatment uses an alkaline source with a pH of 8.5-9 to further remove residual fluorides and ensure that the emission concentration is ≤1 mg / m³. 3 The exhaust gas pipeline heat tracing and insulation method used in this invention (≥120℃) employs a large-curvature elbow design to prevent electrolyte condensation and pipe blockage.

[0101] S3 Whole Pack Crushing: The intermediate battery pack is subjected to multi-stage crushing to obtain crushed material.

[0102] The multi-stage crushing process includes: primary crushing of the intermediate battery pack to obtain coarse crushed material, and secondary crushing of the coarse crushed material to obtain the crushed material. Specifically, the primary crushing can employ a four-axis shredder or other conventional crushing devices used by those skilled in the art. When using a four-axis shredder, the rotation speed is adjusted to 120~180 r / min, the cutter head spacing is 5 mm, and the average particle size of the entire battery pack after primary crushing is ≤100 mm. During the primary crushing process, by adjusting the rotation speed of the four-axis cutter head, it can process pouch cells (thickness 5~10 cm), prismatic cells (size 200×100×50 mm), and small modules (size 500×300×200 mm), achieving full type compatibility with a jamming rate of ≤1%, significantly increasing the processing capacity, and covering more than 95% of commercial battery pack forms. For pouch cells, the particle size of the coarse crushed material after the above-mentioned crushing can prevent adhesion; for prismatic cells, the particle size of the coarse crushed material after the above-mentioned crushing can prevent jamming; and for small modules, it can effectively prevent entanglement. The secondary crushing can be performed using a single-shaft crusher or other crushing devices conventional to those skilled in the art. When using a single-shaft crusher, the rotational speed is adjusted to 180~220 r / min, and the crushing gap is 3 mm. After secondary crushing, the coarse material achieves an average particle size of ≤50 mm to meet subsequent sorting requirements.

[0103] Furthermore, both the primary and secondary crushing processes undergo water cooling and nitrogen protection. Water cooling avoids the risk of temperature rise due to aluminum shavings friction. Cold water circulation can be used to cool the bearings of the crushing device, preferably with an inlet water temperature ≤30℃ and an outlet water temperature ≤45℃. The temperature inside the crushing chamber is monitored in real time, and the crushing device will automatically shut down when it exceeds 45℃. Nitrogen protection involves introducing nitrogen at a flow rate of 120~150 m³ / h into the inlet of the crushing device to prevent oxygen from entering and causing oxidation of metallic products such as aluminum shavings. In addition, the nitrogen discharged from the crushing device can be treated as exhaust gas to prevent pollution caused by pollutants carried by the nitrogen.

[0104] Traditional crushing-then-drying processes increase the specific surface area of ​​the material after crushing, resulting in dust generation of ≥15kg / ton and a bag filter clogging frequency of up to once every 3 days. Although some processes have added a dust cleaning spiral, weekly shutdowns are still required for cleaning, affecting uptime. This invention adopts a drying-then-crushing process, resulting in a material moisture content of ≤0.5% after drying and reducing dust generation during crushing to ≤6kg / ton. Simultaneously, the exhaust gas system of this invention reduces dust and electrolyte levels in the sorting process at the source. Dust is removed first through high-temperature dust removal before subsequent processing, reducing clogging frequency to once every 30 days and lowering maintenance costs by 60%. The single-line annual processing capacity can reach 50,000 tons, five times that of traditional single-cell battery processing, meeting the needs of large-scale recycling bases.

[0105] S4 sorting process: The crushed material is subjected to multi-stage precision sorting to obtain black powder product.

[0106] The multi-stage precision sorting method includes: primary sorting of the crushed material to obtain coarse particles and battery cell fragments, separating the coarse particles; secondary sorting of the battery cell fragments to obtain mixed fragments and primary black powder, separating the primary black powder; and tertiary sorting of the mixed fragments to obtain metallic materials and black powder products, separating the metallic materials. Specifically, the primary sorting can use a linear screen or other commonly used screen devices in the art, controlling the screen aperture to 8-12mm to screen out coarse particles, including crushed particles of the outer shell and electrode, with a weight percentage of 15-18%. The coarse particles are separated from the aluminum outer shell (purity ≥95%) by a baffle separator (wind speed 5m / s). The secondary sorting can first use a hammer crusher (speed 1500r / min) to break up the battery cell fragments, and then use a circular vibrating screen or other commonly used screen devices in the art to screen them, controlling the screen aperture to 4-6mm to screen out the primary black powder, with a yield of 60-65% and a purity ≥97%. The three-stage sorting can employ a gravity separator or other commonly used screen devices in the art, with a screen aperture of 1-2 mm, to sort the mixed fragments containing copper and aluminum foil and residual black powder, thereby removing metallic materials such as copper powder and aluminum powder, with the copper powder purity ≥96% and the aluminum powder purity ≥95%. Further, the primary black powder is purified to obtain a black powder product. Specifically, the purification process can employ an ultrasonic vibrating screen or other commonly used screen devices in the art to remove impurities, controlling the screen aperture to 0.1-0.2 mm to remove fine copper and aluminum particles, with a final black powder yield ≥98%, the residual black powder content in the copper and aluminum slag ≤0.5% (lithium content ≤0.3%), and the copper ≤0.8% and aluminum ≤0.7% in the black powder.

[0107] In some embodiments, the battery pack recycling method includes:

[0108] S01: Obtain basic information about the battery pack and build a parameter database that automatically matches the operating parameters of the pretreatment, whole pack gradient pyrolysis, whole pack crushing, sorting and processing and exhaust gas co-treatment processes for different battery packs.

[0109] S02: Real-time operating parameters collected during the pretreatment, whole-package gradient pyrolysis, whole-package crushing, sorting and treatment and exhaust gas co-treatment processes.

[0110] S03: Based on real-time operating parameters and parameter database, the operating parameters of pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting and treatment and exhaust gas co-treatment are linked and controlled.

[0111] For example, the basic information of the battery pack includes, but is not limited to, the battery pack model, capacity, and retirement time. The operating parameters of the pretreatment process include, but are not limited to, the discharge voltage of the battery cells. The operating parameters of the whole-pack gradient pyrolysis process include, but are not limited to, temperature and pressure. The operating parameters of the whole-pack crushing process include, but are not limited to, the rotational speed of the crushing equipment. The operating parameters of the sorting process include, but are not limited to, the rotational speed and frequency of the sorting equipment. The operating parameters of the exhaust gas co-treatment include, but are not limited to, the concentration of pollutants in the exhaust gas. It should be noted that those skilled in the art can add other basic information and operating parameters of the battery pack according to the design concept of this invention to make the linkage control process more refined.

[0112] To enable those skilled in the art to fully understand the operation of this invention, the present invention provides the following exemplary implementation methods regarding the control of operating parameters: For battery packs with a capacity ≥150kW, the pyrolysis time and the number of pulse discharge cycles are adjusted and extended; for lithium iron phosphate battery packs, the low-temperature drying temperature is increased by 10~15℃. When the temperature of the entire pack pyrolysis treatment is lower than the preset temperature threshold of 5℃ in the parameter database, the heating power is automatically increased by 10%~15%, and the nitrogen flow rate is simultaneously fine-tuned; when the VOCs concentration in the exhaust gas is higher than the preset concentration threshold of 12mg / m³ in the parameter database, the adsorption tower fan speed is increased by 15%, and the activated carbon adsorption residence time is extended.

[0113] Furthermore, the present invention also includes: preset multi-scenario fault thresholds; acquiring temperature, pressure, oxygen content, and flow parameters; and based on the acquired parameters and corresponding fault thresholds, performing fault judgment and early warning for the pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting, and exhaust gas co-treatment processes, and triggering automatic emergency handling. For example, in the pretreatment stage: if the cell voltage equalization deviation is >0.3V, the system automatically pauses discharge and starts the equalization circuit. In the whole-pack gradient pyrolysis stage: if the temperature rises sharply by >10℃ / min, the heating source is automatically cut off, and the nitrogen flow rate is increased by 50%.

[0114] In another specific embodiment, the present invention provides a battery pack recycling and processing device system, which is used in a battery pack recycling and processing method described in a specific embodiment. The system includes a pretreatment unit, a pyrolysis unit, a crushing unit, and a sorting unit connected sequentially along the battery pack conveying direction. The pretreatment unit includes a voltage equalization regulating device, a whole-pack discharge device, and a cap removal device connected sequentially along the battery pack conveying direction. The pyrolysis unit includes a continuous pyrolysis device, which includes a low-temperature zone, a medium-temperature zone, and a high-temperature zone arranged sequentially. The crushing unit includes a multi-stage crushing device. The sorting unit includes a multi-stage sorting device.

[0115] In some embodiments, the battery pack recycling and processing device system further includes a tail gas treatment unit connected to the pyrolysis unit. Specifically, the tail gas treatment unit includes a dust removal device, an incineration device, a cooling device, an acid removal device, and an alkali spraying device connected in sequence. The incineration device is externally connected to a waste heat recovery device. The tail gas pipes connecting the various devices are insulated with 50mm rock wool and electrically heated (temperature ≥120℃), and the elbows are designed with a large curvature (curvature radius ≥3 times the pipe diameter) to reduce dust accumulation. Specifically, the dust removal device can use ceramic filter tubes; the incineration device can be a secondary combustion chamber; the waste heat recovery device can be a waste heat boiler; the cooling device can be a quench tower; the acid removal device can be an acid removal tower; and the alkali spraying device can be an alkali spraying tower.

[0116] In some embodiments, the pretreatment unit further includes a supplementary discharge device disposed between the package discharge device and the cap removal device.

[0117] Furthermore, the pretreatment unit also includes a pumping device, a wire harness removal device, and a punching device connected in sequence. The inlet end of the pumping device is connected to the cap removal device, and the outlet end of the punching device is connected to the pyrolysis unit.

[0118] In some embodiments, the continuous pyrolysis apparatus may be a continuous tunnel kiln, which has the function of independent temperature control and nitrogen flow regulation in different zones, and uses a fluorine-resistant lining.

[0119] In some embodiments, the multi-stage crushing device includes a primary crushing device and a secondary crushing device connected in sequence. The primary crushing device is connected to the pyrolysis unit, and the secondary crushing device is connected to the sorting unit. Further, the primary crushing device and the secondary crushing device are each independently equipped with a cooling assembly and a nitrogen protection assembly. The primary crushing device and the secondary crushing device each independently include any one or a combination of at least two of the following: a linear screen, a circular vibrating screen, a gravity separator, or an ultrasonic gyratory screen.

[0120] In some embodiments, the multi-stage sorting device includes a primary sorting device, a secondary sorting device, a tertiary sorting device, and a purification device, wherein the primary sorting device is connected to the crushing unit. The outlet of the purification device can be connected to a collection device for collecting the black powder product.

[0121] In some embodiments, the battery pack recycling and processing device system further includes an intelligent control unit, which is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit. Specifically, the intelligent control unit includes a data acquisition module, a parameter calculation module, and a control module. The data acquisition module is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit to acquire basic battery pack information and real-time operating parameters of each processing unit. The parameter calculation module is electrically connected to the data acquisition module and the control module to construct a parameter database based on the basic battery pack information and automatically match the standard operating parameters of the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit. The control module is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit to adjust the operating parameters of the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit.

[0122] Furthermore, the battery pack recycling and processing device system also includes a fault early warning unit. This unit is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit, respectively. It is used to determine whether any processing unit has malfunctioned, issue an early warning based on the determination result, and automatically execute emergency procedures. The fault early warning unit has functions such as automatic nitrogen replenishment when oxygen content exceeds the limit, automatic shutdown protection in case of abnormal temperature, dynamic adjustment of nitrogen flow rate based on processing volume, and remote data upload and historical record query functions.

[0123] Example 1

[0124] This embodiment provides a battery pack recycling method for recycling retired LFP battery packs from new energy vehicles (each pack weighs 1.2t, has an initial SOC of 32%, and measures 1.8m × 0.8m × 0.4m, with prismatic cells). Figure 1 As shown, the specific steps include the following:

[0125] (1) Pre-treatment of the entire battery pack

[0126] Whole pack voltage equalization adjustment: Detect the voltage value of each cell in the whole battery pack to obtain the voltage deviation between cells. Determine whether the voltage deviation is greater than 0.3V. If so, start the equalization circuit (adjust current ≤0.1C) to adjust the voltage of the cells in the battery pack. After controlling the voltage deviation to ≤0.1V, the whole pack is discharged. Otherwise, the whole pack is discharged directly.

[0127] Full pack discharge: Each battery pack is connected to a discharge device and discharged at a current of 60A for 2.5 hours until the voltage drops to 2.9V. For battery packs that do not meet the requirements and have a voltage > 3.0V, they are discharged at a current of 40A for 1 hour until the voltage drops to 2.85V.

[0128] Removal of cover: The top cover of the battery pack is removed using a laser, resulting in a coverless battery pack.

[0129] Coolant draining: Drain the coolant from the battery pack at a rate of 6L / min under negative pressure.

[0130] Wiring harness removal: A robotic arm is used to remove the battery pack BMS assembly and high and low voltage wiring harnesses.

[0131] Safety valve puncture: An automatic puncture machine is used to puncture the battery pack safety valve to form a through hole with a diameter of 2mm.

[0132] (2) Gradient pyrolysis of the whole package

[0133] Continuous tunnel kiln preheating: The low temperature zone of the tunnel kiln is heated to 100℃ and nitrogen gas is introduced at a rate of 60 m³ / h; the medium temperature zone is heated to 250℃ and nitrogen gas is introduced at a rate of 70 m³ / h; the high temperature zone is heated to 350℃ and nitrogen gas is introduced at a rate of 90 m³ / h; and the oxygen content inside the tunnel kiln is stabilized at 2.4%.

[0134] Material conveying: 10 bags / batch (12t) are fed into the continuous tunnel kiln via a chain conveyor belt at a speed of 4m / h.

[0135] Low-temperature drying: The battery pack is kept in a low-temperature zone for 35 minutes for low-temperature drying to selectively evaporate the electrolyte.

[0136] Medium-temperature debonding: The battery pack is kept in the medium-temperature zone for 30 minutes to remove the decomposition products of the adhesive.

[0137] High-temperature pyrolysis: The battery pack is placed in a high-temperature zone for 25 minutes for high-temperature pyrolysis to deeply decompose the binder, thereby reducing the water content of the battery pack to 0.5%.

[0138] Process monitoring: Real-time recording of kiln temperature (fluctuation ≤8℃), pressure (-90Pa), oxygen content (2.4%), and the generated pyrolysis gas flow rate is stable at 12000m³ / h.

[0139] (3) The whole package was broken.

[0140] Primary crushing: The pyrolyzed battery pack is fed into a four-shaft shredder for crushing to obtain coarse crushed material with an average particle size of ≤100mm. At the same time, water cooling and nitrogen protection are carried out. The inlet water temperature for water cooling is 30℃, the outlet water temperature is 41℃, and the nitrogen flow rate is 135m³ / h to ensure that the temperature inside the crushing chamber of the four-shaft shredder is 39~42℃.

[0141] Secondary crushing: The coarse crushed material is transferred to a single-shaft crusher for crushing to obtain crushed material with an average particle size of ≤50mm. At the same time, water cooling and nitrogen protection are carried out. The inlet water temperature for water cooling is 30℃, the outlet water temperature is 41℃, and the nitrogen flow rate is 135m³ / h.

[0142] (4) Sorting process

[0143] Primary sorting: The crushed material is passed through a linear screen with a screen aperture of 10mm to obtain coarse particles and battery cell fragments. The coarse particles, namely the aluminum shell, are separated.

[0144] Secondary sorting: After the battery cell fragments are broken up by a hammer crusher, they are passed through a circular vibrating screen with a screen aperture of 5mm to obtain mixed fragments and primary black powder, and the primary black powder is separated.

[0145] Three-stage sorting: A gravity separator is used to separate the mixed crushed materials to obtain metal materials and black powder products, separating the metal materials, namely copper powder and aluminum powder.

[0146] Purification process: The primary black powder is passed through an ultrasonic oscillating sieve with a sieve aperture of 0.15 mm to remove impurities and obtain the black powder product, in which the copper content is 0.2% and the aluminum content is 0.3%.

[0147] (5) Exhaust gas system treatment

[0148] The pyrolysis gas undergoes a series of treatments, including high-temperature dust removal, incineration, waste heat recovery, rapid cooling, tail gas deacidification, and alkaline scrubbing. The high-temperature dust removal temperature is set at 420℃, the incineration temperature at 900℃, and the residence time at 10s. Waste heat recovery generates 0.8MPa steam, which rapidly cools the pyrolysis gas, reducing its temperature from 850℃ to below 200℃ within 2s, thus inhibiting dioxin formation. Tail gas deacidification is achieved by spraying lime onto the pyrolysis gas. During the alkaline scrubbing process, the pH is controlled at 9, resulting in a 99.95% removal rate of organic pollutants from the pyrolysis gas.

[0149] Comparative Example 1

[0150] This comparative example provides a battery pack recycling method for recycling retired LFP battery packs from new energy vehicles (each pack weighs 1.2t, has an initial SOC of 32%, and measures 1.8m × 0.8m × 0.4m, with square-shaped cells). The difference from Example 1 is that in the pretreatment process of the battery pack, the entire battery pack is disassembled, and the disassembled batteries are sequentially subjected to crushing, pyrolysis, and sorting processes.

[0151] Compared to Example 1, Comparative Example 1 requires expensive dismantling equipment, involves complex dismantling processes, and generates a large amount of dust during recycling, resulting in a higher concentration of copper and aluminum impurities in the final black powder product, thus reducing the purity of the final product. Example 1, however, eliminates the need for pre-dismantling of the battery pack, saving on individual cell dismantling equipment and reducing depreciation costs by 20%. Furthermore, Example 1 employs a drying-then-crushing sequence, reducing dust generation during crushing to ≤6 kg / ton and material jamming rate to ≤1%. Multi-stage precision sorting further ensures a black powder yield of ≥98% and copper and aluminum slag residue of ≤0.5%. In addition, Example 1 has a single-line annual processing capacity of up to 50,000 tons, five times that of Comparative Example 1's individual battery processing capacity, meeting the needs of large-scale recycling facilities.

[0152] Comparative Example 2

[0153] This comparative example provides a battery pack recycling method for recycling retired LFP battery packs from new energy vehicles (each pack weighs 1.2t, has an initial SOC of 32%, and measures 1.8m × 0.8m × 0.4m, with prismatic cells). The difference from Example 1 is that no staged pyrolysis is performed. The pyrolysis process of the battery pack is kept at a constant temperature of 700°C throughout. The generated pyrolysis gas is cooled and the organic solvent is recovered. The remaining steps and process parameters are the same as in Example 1.

[0154] Compared to Example 1, Comparative Example 2 uses a one-stage high-temperature pyrolysis, which excessively decomposes the low-boiling-point solvents within the battery pack, and some valuable metals in lithium iron phosphate oxidize at high temperatures, reducing the recovery rate. Example 1 employs an integrated gradient pyrolysis process for the entire battery pack, using a three-stage process of low-temperature drying + medium-temperature debinding + high-temperature pyrolysis. Different solvents are decomposed at different temperature stages, resulting in a lower overall temperature and preventing metal oxidation. Furthermore, Example 1 directly purifies the generated pyrolysis gas and recovers steam from waste heat during the exhaust gas co-treatment process, saving annual energy costs. The comprehensive treatment cost is 1455.5 yuan / ton, significantly lower than traditional processes, achieving a synergy of high yield and low cost. It also effectively removes low-boiling-point VOCs (Volatile Organic Compounds) and fluorides from the flue gas, avoiding secondary pollution.

[0155] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for recycling and processing battery packs, characterized in that, The battery pack recycling method includes: S1 Pre-processing: The battery pack is subjected to voltage equalization adjustment, full pack discharge and cover removal in sequence to obtain a coverless battery pack; S2 Gradient Pyrolysis of the Whole Pack: The uncovered battery pack is sequentially subjected to low-temperature drying, medium-temperature debinding and high-temperature pyrolysis to obtain an intermediate battery pack and pyrolysis gas; S3 Whole Pack Crushing: The intermediate battery pack is subjected to multi-stage crushing to obtain crushed material; S4 sorting process: The crushed material is subjected to multi-stage precision sorting to obtain black powder product.

2. The battery pack recycling method according to claim 1, characterized in that, The voltage equalization adjustment includes: The voltage value of each cell in the battery pack is detected to obtain the voltage deviation between cells; Determine if the voltage deviation is greater than the preset voltage difference. If so, start the equalization circuit to adjust the voltage of the cells in the battery pack until the voltage deviation does not exceed the standard voltage difference, then discharge the entire battery pack. Otherwise, discharge the entire battery pack directly. And / or, the preset voltage difference is 0.2~0.3V; And / or, the standard voltage difference is 0.1~0.2V; And / or, the whole-pack discharge includes pulsed discharge processing; And / or, the current of the pulse discharge treatment is 50~80A; And / or, the pulse discharge treatment lasts for 2-3 hours; And / or, after the pulse discharge process ends, the voltage of the battery pack is 2.8~3V.

3. The battery pack recycling method according to claim 1 or 2, characterized in that, The preprocessing also includes: after the entire pack is discharged, performing a supplementary discharge process on the battery pack with a voltage value greater than 3V, and detecting the voltage of each cell in the battery pack to ensure that its voltage is less than 3V. And / or, the current for the supplementary discharge treatment is 30~50A; And / or, the pretreatment further includes: sequentially draining coolant from the uncovered battery pack, removing wiring harnesses, and punching holes in the safety valve; And / or, the pumping rate of the coolant is 5~8L / min; And / or, the wiring harness removal includes removing the battery pack BMS assembly from the high and low voltage wiring harnesses; And / or, the diameter of the through hole formed by punching the safety valve is 2~3mm.

4. The battery pack recycling method according to any one of claims 1-3, characterized in that, The low-temperature drying, the medium-temperature debonding, and the high-temperature pyrolysis are each independently performed by purging the uncovered battery pack with nitrogen gas. And / or, the temperatures and nitrogen flow rates of the low-temperature drying, the medium-temperature debonding, and the high-temperature pyrolysis are different; And / or, the temperature of the low-temperature drying is 80~120℃; And / or, the low-temperature drying time is 30~40 min; And / or, the nitrogen flow rate for the low-temperature drying is 50~60 m³ / h; And / or, the temperature for the intermediate-temperature debonding is 200~280℃; And / or, the medium-temperature debonding time is 25~35 min; And / or, the nitrogen flow rate for the intermediate-temperature debonding is 70~80 m³ / h; And / or, the temperature of the high-temperature pyrolysis is 300~400℃; And / or, the high-temperature pyrolysis time is 20~30 min; And / or, the nitrogen flow rate for the high-temperature pyrolysis is 90~100 m³ / h; And / or, the moisture content of the intermediate battery pack is ≤0.5%.

5. The battery pack recycling method according to any one of claims 1-4, characterized in that, The battery pack recycling method further includes: co-treating the pyrolysis gas with exhaust gas before discharging it; And / or, the exhaust gas co-treatment includes high-temperature dust removal, incineration, waste heat recovery, rapid cooling, and exhaust gas deacidification and alkali spraying treatment performed sequentially. And / or, the temperature of the high-temperature dust removal is 400~420℃; And / or, the incineration treatment temperature is ≥850℃, and the residence time is >2.5s; And / or, after the rapid cooling is completed, the temperature of the pyrolysis gas is below 200°C; And / or, the tail gas deacidification includes spraying lime onto the pyrolysis gas; And / or, the pH of the alkali source used in the alkali spraying treatment is 8.5~9.

6. The battery pack recycling method according to any one of claims 1-5, characterized in that, The battery pack recycling method further includes: Obtain basic information about the battery pack and build a parameter database that automatically matches the operating parameters of the pretreatment, whole pack gradient pyrolysis, whole pack crushing, sorting and processing and exhaust gas co-treatment processes for different battery packs. Real-time operating parameters are collected during the pretreatment, whole-package gradient pyrolysis, whole-package crushing, sorting and treatment and exhaust gas co-treatment processes; Based on real-time operating parameters and parameter database, the operating parameters of pretreatment, whole-pack gradient pyrolysis, whole-pack crushing, sorting and treatment and exhaust gas co-treatment are linked and controlled.

7. The battery pack recycling method according to any one of claims 1-6, characterized in that, The multi-stage crushing process includes: performing primary crushing on the intermediate battery pack to obtain coarse crushed material, and performing secondary crushing on the coarse crushed material to obtain the crushed material; And / or, the average particle size of the coarse crushed material is ≤100mm; And / or, the average particle size of the crushed material is ≤50mm; And / or, water cooling and nitrogen protection are performed during both the primary crushing and the secondary crushing processes; And / or, the inlet water temperature of the water cooling treatment is ≤30℃ and the outlet water temperature is ≤45℃; And / or, the nitrogen flow rate used for nitrogen protection is 120~150m³ / h.

8. The battery pack recycling method according to any one of claims 1-7, characterized in that, The aforementioned multi-level precise sorting includes; The crushed material is first-stage sorted to obtain coarse particles and battery cell fragments. The coarse particles are separated, and the battery cell fragments are second-stage sorted to obtain mixed fragments and primary black powder. The primary black powder is separated, and the mixed fragments are third-stage sorted to obtain metallic materials and black powder products. The metallic materials are separated. And / or, the screen mesh used in the primary sorting has an aperture of 8~12mm; And / or, the screen mesh used in the secondary sorting has an aperture of 4~6mm; And / or, the screen mesh used in the three-stage sorting has an aperture of 1~2mm; And / or, the multi-stage precision sorting further includes: purifying the primary black powder to obtain a black powder product; And / or, the sieve mesh size used in the purification process is 0.1~0.2mm; And / or, the copper content in the black powder product is ≤0.8%, and the aluminum content is ≤0.7%.

9. A battery pack recycling and processing device system, characterized in that, The battery pack recycling and processing device system is used in the battery pack recycling and processing method according to any one of claims 1-8. The battery pack recycling and processing device system includes a pretreatment unit, a pyrolysis unit, a crushing unit and a sorting unit connected in sequence along the battery pack conveying direction. The pretreatment unit includes a voltage equalization adjustment device, a whole pack discharge device and a cover removal device connected in sequence along the battery pack conveying direction. The pyrolysis unit includes a continuous pyrolysis device, which includes a low-temperature zone, a medium-temperature zone, and a high-temperature zone arranged sequentially. The crushing unit includes a multi-stage crushing device; The sorting unit includes a multi-stage sorting device.

10. The battery pack recycling and processing device system according to claim 9, characterized in that, The battery pack recycling and processing device system also includes an intelligent control unit, which is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit and the sorting unit respectively; And / or, the intelligent control unit includes a data acquisition module, a parameter calculation module, and a control module. The data acquisition module is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit, respectively, and is used to acquire basic battery pack information and real-time operating parameters of each processing unit. The parameter calculation module is electrically connected to the data acquisition module and the control module, respectively, and is used to construct a parameter database based on the basic battery pack information and automatically match the standard operating parameters of the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit. The control module is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit, respectively, and is used to adjust the operating parameters of the pretreatment unit, the pyrolysis unit, the crushing unit, and the sorting unit. And / or, the battery pack recycling and processing device system further includes an exhaust gas treatment unit, which is connected to the pyrolysis unit; And / or, the exhaust gas treatment unit includes a dust removal device, an incineration device, a cooling device, an acid removal device and an alkali spraying device connected in sequence, and the incineration device is externally connected to a waste heat recovery device; And / or, the pretreatment unit further includes a supplementary discharge device disposed between the package discharge device and the cap removal device; And / or, the pretreatment unit further includes a pumping device, a wire harness removal device and a punching device connected in sequence, the inlet end of the pumping device is connected to the cap removal device, and the outlet end of the punching device is connected to the pyrolysis unit; And / or, the multi-stage crushing device includes a primary crushing device and a secondary crushing device connected in sequence, wherein the primary crushing device is connected to the pyrolysis unit and the secondary crushing device is connected to the sorting unit; And / or, the primary crushing device and the secondary crushing device are each independently equipped with a cooling component and a nitrogen protection component; And / or, the multi-stage sorting device includes a primary sorting device, a secondary sorting device, a tertiary sorting device and a purification device, wherein the primary sorting device is connected to the crushing unit; And / or, the battery pack recycling and processing device system further includes a fault early warning unit, which is electrically connected to the pretreatment unit, the pyrolysis unit, the crushing unit and the sorting unit respectively.

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